A 51-year-old female ex-smoker with a history of hypertension, hepatitis C, and HIV on highly active anti retroviral therapy was referred to cardiology clinic for an exercise stress echocardiogram to evaluate atypical chest pain. Resting blood pressure (BP) was 137/97 mmHg. The electrocardiogram (ECG) was notable for a normal sinus rhythm with a rate of 63 beats per minute (bpm), normal axis, and RSR' in V1 with T-wave inversion (Figure 1A). She performed exercise on an exercise bike (Ergometer). Definity contrast was administered at rest and stress for endocardial border definition. Peak heart rate was 141 bpm (83.4% of predicted) and peak BP was 136/100 mmHg. The test was terminated secondary to shortness of breath and leg fatigue. The patient did not experience any chest pain during exercise or recovery. The patient developed up to 2.5 mm acute ST segment elevation in leads V1-V3 during exercise that persisted into the recovery phase (Figure 1B and 1C). RSR pattern became more prominent and extended to leads V1 and V2 (Figure 1B and 1C). Additionally, the height of the P wave in lead II increased during exercise and persisted during recovery. The normal axis at baseline shifted to a rightward axis during the recovery phase, as suggested by more prominent S waves in lead I, V5 and V6 (Figure 1B and 1C).
The resting echocardiogram revealed a normal left ventricle (LV) with an estimated ejection fraction of 65% and wall motion was also normal in all segments (Figure 2A; Additional files 1, 2). There was mild to moderate right ventricular (RV) enlargement and hypertrophy. A saline contrast study did not reveal intracardiac shunting. There was normal valve function. Pulmonary artery systolic pressure (PASP) was estimated at 46 mmHg (Figure 3A). At peak exercise and in the immediate recovery phase, there was marked RV enlargement and interventricular septum flattening (Figure 2B; Additional files 3, 4). The peak PASP was estimated to be 81 mmHg during exercise and 101 mmHg immediately afterwards (Figures 3B and 3C). Wall motion was hyperkinetic in all LV segments and the ejection fraction was 80%. There was no increase in mitral regurgitation during exercise.
Additional file 1: Resting echocardiogram in the parasternal short axis view. Parasternal short axis at rest showing normal LV wall motion and LV systolic function. The RV is mildly to moderately enlarged and hypertrophied. (MPEG 200 KB)
Additional file 2: Resting echocardiogram in the apical 4 chamber view. Apical 4 chamber view at rest showing normal LV wall motion and ejection fraction. The RV is mildly to moderately enlarged and hypertrophied. (MPEG 284 KB)
Seven weeks later, the patient underwent a cardiac catherization. Left heart catherization revealed normal coronary arteries and LV systolic function. There was no coronary vasospasm during the angiogram. On right heart catherization, the resting mean PAP was 41 mmHg and PASP was 74 mmHg (Figure 4). Pulmonary capillary wedge pressure was 7 mmHg. The mean PAP decreased to 31 mmHg following administration of nitric oxide. After exercise, the mean PAP increased to 49 mmHg and PASP was 86 mmHg.